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AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

Product code : DHDQT-EA

4.9 star rating Read 1,543 reviews

Customer Rating

4.9

92% would recommend

  • 5 1478
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,543 reviews
  • 5 star rating
    By  Edgar Fernández ,  a  Verified Buyer  from  Fremont,CA  on  October 15, 2020
    Great oil!!! It does really well with temperatures. It maintains its additives and its viscosity really well. Very good oil sample results using this oil. My car has currently 348,000miles and still running strong. I have been using amsoil for all my oil changes. Amazing oil and results.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2006 duramax 2500 HD 6.6 liter lbz
    By  Mike Clary,  a  Verified Buyer  from  San Antonio, Texas  on  October 15, 2020
    Very satisfied with this product, I highly recommend it !!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature Diesel 5W-40
    By  Rusty,  a  Verified Buyer  from  Calgary Canada  on  October 15, 2020
    I've been using Amsoil signature oil in all my vehicles for years and just switch from another Synethic oil that the dealer used in my 6.7 Cummins. It has excellent oil properties and provides excellent lubrication under extreme -25c weather up tp 40c we experienced in summer hauling. For my money it provides that extra assurance and piece of mind.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    You can hear the difference
    By  Hard Puller,  a  Verified Buyer  from  Cartwright, ND  on  October 15, 2020
    My engine was the first component on my new 2020 Ford F450 that got changed out to Amsoil. I do my own service work and when I finished the oil change including the Amsoil filter, I started my rig up and couldn’t believe how much quieter the engine sounded. That same day I ordered all of the Amsoil required to change every component on my truck. My transmission is running about 20 degrees cooler in a hard pull and the transfer case and the front and rear differentials noise level also dropped. I also gain about 2 miles per gallon in fuel consumption. This is going to be my last rig I buy as I will be retiring soon, I’m going to make sure it gets the best care to make sure.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    diesel oil
    By  paul,  a  Verified Buyer  from  Texas  on  October 15, 2020
    I have used other diesel oil in my trucks, suvs, tractors, back holes and even some cars. I have found that amsoil performs better then almost all the other brands. I just know that out of all the oils I have used amsoil works better in all condition I have run into. The price of the oil cost as much as the rest of the diesel oils it just holes up better and amsoil oil filter cleans oil better. I have been using amsoil for over thirty years and still like it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I like the Synthetic Oils from Amsoil the best
    By  Randy ,  a  Verified Buyer  from  Williston , Vermont  on  October 15, 2020
    The Amsoil Synthetics are so much better ,I get outstanding results using there Synthetic Oils . The 5W-40 Synthetic Oil for the Diesel engine is the best to use all winter, the engine starts easier in winter months and runs cooler engine Temps even in the summer hot days . There Synthetics provide easier starting in the cold days of winter as well as keeping all engine parts running easier ( Less Friction ) on those cold days and less friction and less heat build on the warmer or hotter days of summer . You can see lower engine temps in the summer when running , less friction on those metal parts means better mileage and less wear . I like all there Amsoil synthetic oils and greases. If you're not using the Amsoil Synthetics your wasting your money on the other oils you should be using there Synthetic Oils at Amsoil and seeing the difference it makes on your equipment by running better their Synthetic Oils are much slipper on all metal moving parts .
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    great oil
    By  cp,  a  Verified Buyer  from  Cody wy  on  October 15, 2020
    used in three trucks oldest an 01 with 275k purrs like a kitten
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  • 5 star rating
    By  Ray,  a  Verified Buyer  on  October 15, 2020
    Using Amsoil motor oil for years,always count on the quality
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  October 15, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  October 15, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  Trigger ,  a  Verified Buyer  from  Texas   on  October 15, 2020
    So far I really like the oil. , it seams to be staying thicker
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 24, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 20, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  Chery,  a  Verified Buyer  from  Lompoc   on  September 20, 2020
    Great price
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Diesel oil available!
    By  Baldeagle535,  a  Verified Buyer  from  New Mexico  on  September 20, 2020
    This product performs as advertised and tested. The engine starts easily in cold weather; it runs cool in hot weather. It protects the engine against excessive wear. I am a happy customer after using it in two different diesel engines.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 17, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Product Review
    By  Eastern Light Fisheries. ,  a  Verified Buyer  from  Montauk, N.Y.  on  September 17, 2020
    Best diesel oil on the market...!!!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  JBC,  a  Verified Buyer  from  La.   on  September 16, 2020
    Very good oil 15W40 SS Diesel oil is all i run in my duramax trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2003 Dodge Ram 3500
    By  Gimpy ,  a  Verified Buyer  from  Washington State   on  September 16, 2020
    Amsoil is the only brand I run in my vehicles and with extended drain intervals and proven results it’s a no brainer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  September 16, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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